= coxeter3 =

== Description ==

This package wraps Fokko Ducloux's Coxeter 3 C++ library

Features:

- General Coxeter groups, implemented through the combinatorics of reduced words;
- Reduced expression and normal form computations;
- Bruhat ordering;
- Ordinary Kazhdan-Lusztig polynomials;
- Kazhdan-Lusztig polynomials with unequal parameters;
- Inverse Kazhdan-Lusztig polynomials;
- Cells and W-graphs;

http://math.univ-lyon1.fr/~ducloux/coxeter/coxeter3/english/coxeter3_e.html

== License ==

GPL

== SPKG Maintainers ==

* Mike Hansen

== Upstream Contact ==

None; alas, Fokko Ducloux passed away in 2006.

http://math.univ-lyon1.fr/~ducloux/du_Cloux.html

== Dependencies ==

None

== Special Update/Build Instructions ==

Upstream is unlikely to change, unless someone takes over the
development of Coxeter3. In any cases, the application of the
following patches is automatically handled by spkg-install:

- directories.h.patch: update coxeter3 directory information to fetch
  its data and messages from the Sage installation tree
- makefile.patch: handle compilation flags for Darwin and Cygwin
- sage.cpp: add a function for Bruhat invervals which is simpler to
  code in C++ than Cython

== Changelog ==

=== coxeter3-1.1 (Mike Hansen 2009-2013 + some fixes by Nicolas M. Thiéry and Jean-Pierre Flori) ===

 * Initial release. See Sage trac #12912
